Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
(Pl. 5a): holotype, Hampden Beach, North Otago, Bortonian (TM4117, GNS)
(Pl. 5b): holotype, Hampden Beach, North Otago, Bortonian (TM4117, GNS)
Beu & Maxwell (1990): Chapter 7; p. 100; pl. 5 a, b.
Synonymy: Sarepta solenelloides Marshall 1919, p. 233; Nuculana (Pseudoportlandia) solenelloides
Classification: Nuculanidae: Nuculaninae
Description: Moderately large for family (length 20-27 mm), relatively thick- shelled. Lunule very narrow, lanceolate; escutcheon much broader but weakly differentiated. Commarginal sculpture of linear grooves with broad flat interspaces proximally, rest of shell smooth except for growth ridges. Hinge relatively heavy, anterior series with 17-22, posterior series with 15-19 teeth of chevron cross-section, separated by a deep triangular resilifer. Anterior adductor muscle scar much larger than posterior scar; pallial line with a weak, triangular sinus.
Comparison: Pseudoportlandia tahuia (Kaiatan, McCulloch's Bridge) differs from P. solenelloides by being smaller (maximum length 21 mm), having more steeply descending dorsal margins and having a narrower, more rounded posterior end. Zinsmeister (1984, p. 1504) suggested that P. solenelloides and P. tahuia require a new genus, but until such time as the numerous nuculanid genus-group taxa are thoroughly revised, these species are retained in Pseudoportlandia Woodring, 1924, which is based on a Pliocene Jamaican species [P. clara (Guppy, 1873)]. Pseudoportlandia was long thought to be restricted to the Arnold Series in New Zealand, but it is now considered to include two or three Neogene species as well (Maxwell 1988a, p. 39).
Distribution: Bortonian, Hampden Formation, Hampden Beach, North Otago (type) (common).
Cite this publication as: "A.G. Beu and J.I. Raine (2009). Revised
descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990). GNS
Science miscellaneous series no. 27."
© GNS Science, 2009
(Included with a PDF facsimile file copy of New Zealand Geological Survey Paleontological Bulletin 58 in CD version from: Publications Officer, GNS Science, P.O. Box 30368 Lower Hutt, New Zealand)